The quality of our YarnMaster yarn clearers is unique. Through the reliable and variable detection of yarn faults, the desired yarn quality can be manufactured while fulfilling highest requirements on efficiency. This ensures adaption to fast changing fashion trends and customer demands. Open-end spinning mills have relied on the quality of Loepfe’s optoelectronic yarn clearers for many decades.

The trusted choice for rotor yarn clearing

  • Moiré
  • Evenness
  • Spectrogram

Get the most out of rotor yarn

  • Polypropylene
  • Foreign fibers
  • Yarn count

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Since the mid 20th century the so-called rotor spinning or open-end spinning has been developed. The potential of open-end spinning has been steadily increased by the continuous rise in rotor and winding speeds. Rotor-spun yarns have always been successful, where they could be manufactured more cheaply than ring-spun yarns and proved suitable for the range of application in question. The requirements for the raw material differ from ring spinning. For example, open-end spinning usually uses short staple fibers as raw material. With regard to quality control, there is an important difference, too. There is no winding subsequent to the spinning and the quality is monitored directly during the open-end spinning process. Thereby the main focus is to manufacture the desired yarn quality while fulfilling the highest requirements on efficiency. 

Potential Yarn Faults in Open-end Spinning

Open-end spun yarns have various different applications. For the different end products, the yarns are woven or knitted into textile fabrics. In the final fabrics various small yarn faults like NSLT faults, irregularities, piecers and more, can be clearly visible. One of the main threats are periodically occurring variations in the yarn thickness. The typical effect is a moiré pattern in the woven fabric. Tensile strength of the yarn is especially important for subsequent weaving process. Yarn breaks as a result of to low breaking strength caused by thin places will result in reduced efficiency during weaving and lower quality of the woven fabric. For a subsequent knitting process on the other hand, especially thick places are a threat as they can break needles in the knitting machine.

Yarn Clearer in Open-end Spinning

To overcome these threats, Loepfe offers optical yarn clearers, which can be integrated into open-end spinning machines. The yarn clearers 3N1 and 1N1 utilize an optical sensing technology and are able to reliably detect all above mentioned yarn faults. They cover yarn counts from Ne 3 to Ne 60 at a maximum spinning speed up to 400 m/min with one single sensing head.

Our customers know – with Loepfe they see more.